Assembly of a Highly Stable Luminescent Zn₅ Cluster and Application to Bio‐Imaging

Abstract

The assembly sequence of the coordination cluster [Zn 5 (H 2 L n ) 6 ](NO 3 ) 4 ]·8 H 2 O·2 CH 3 OH (Zn 5 ,H 3 L n = (1,2-bis-(benzo[d]imidazol-2-yl)-ethenol) involves in situ dehydration of 1,2-bis(benzo[d]imidazol-2-yl)-1,2-ethanediol (H 4 L) through the formation of the [Zn(H 3 L) 2 ] + monomer,d imerization to [Zn 2 (H 3 L) 2 ] + ,d ehydration of the ligand to [Zn 2 -(H 2 L n ) 2 ] + ,and the final formation of the pentanuclear cluster. The cluster has the following special characteristics:1 )h igh stability in both refluxing 37 %H Cl and 27 %N H 3 ,2 )l ow cytotoxicity,and 3) pH-sensitive fluorescence in the visible-tonear-infrared (Vis/NIR) region in the solid state and in solution. We have applied it as af luorescent probe both in vivo and in vitro.Its H-bonding ability is the key to its affinity and selectivity for imaging lysosomes in HeLa cells and tumors in male BALB/C mice.Itprovides anew type of sensitive and biocompatible fluorescent probe for detecting small tumors (13.5 mm 3 ).Supportinginformation for this article (synthesis, measurement details, crystal data, TG, PXRD, mass spectra, optical spectra, TD-DFT calculations results, and bio-imagingp hotos) can be found under: http://dx.

Photo‐ and pH‐ Dual‐Responsive β‐Cyclodextrin‐Based Supramolecular Prodrug Complex Self‐Assemblies for Programmed Drug Delivery

“…Currently,noncovalent interactions, such as host-guest interactions, [17][18][19][20] hydrogen-bonding interactions, [21][22][23] and metalligand coordination, [24,25] have been utilized to construct various supramolecular complexes (SCs)t hrough the proportional addition of different components.T he completes ynthesis routes can be divided into at least two independent parts, indicatinge fficient synthesis procedures. Furthermore, SCs with ap rocessed amphiphilic nature or responsive properties can self-assemble into different morphologies, such as micelles and vesicles,s ot hat they can be applied in the drug-delivery field.…”